For various purposes of enhancing encoding efficiency in the encoding of a moving image, diversifying methods for accessing a moving image, facilitating the browsing of a moving image, and facilitating the conversion of a file format, inventions according to conventional techniques for structuring a moving image (specifically, rearranging the order of frames, hierarchizing a moving image per shot, and the like) are disclosed in Patent Documents 1 to 5 below.
In a conventional technique disclosed in Patent Document 1, a file generating unit creates editing information representing a rearrangement order for moving image data per frame. Furthermore, an image compressing unit compresses and encodes unedited moving image data based on a difference between frames and then, an output unit transmits the encoded data together with a file of the editing information.
Moreover, in a conventional technique disclosed in Patent Document 2, encoded prediction image data stored in an image-data-stream memory unit is read, to be thus separated into hierarchies by a hierarchy separating unit, according to a hierarchy of a data structure. Next, an image property-extracting unit extracts physical properties, i.e., properties that have generality and reflect content, from the separated hierarchy. Thereafter, an attribute vector-generating unit generates an attribute vector that characterizes each image according to the physical properties. Subsequently, a splitting/integrating unit calculates a distance between the attribute vectors, and then, splits/integrates the attribute vector, so as to automatically structure a picture having a deep hierarchal structure, and an attribute-vector managing unit stores and manages the attribute vector.
Alternatively, a conventional technique disclosed in Patent Document 3 is directed to an automatic hierarchy-structuring method, in which a moving image is encoded, the encoded moving image is split into shots, and then, a scene is extracted by integrating the shots using a similarity of each of the split shots. Moreover, the conventional technique disclosed in Patent Document 3 is also directed to a moving-image browsing method, in which the contents of all of the moving images are grasped using the hierarchy structured data and a desired scene or shot is readily detected.
Furthermore, in a conventional technique disclosed in Patent Document 4, a switching unit sequentially switches video signals on plural channels, picked up by plural cameras, a rearranging unit rearranges the video signals in a GOP unit per channel, an MPEG compressing unit compresses the video signals to be recorded in a recording unit, and further, an MPEG expanding unit expands the video signals per channel, thus compressing a data size so as to store and reproduce the picture data in the input order of each of the channels in total at a predetermined position of plural displaying memories such that a display control unit displays picture data on multiple screens, whereby an image output unit displays the multiple screens on one screen of a monitor.
Moreover, in a conventional technique disclosed in Patent Document 5, a size converting unit converts a reproduced moving-image signal A2 obtained by decoding, by an MPEG-2 decoder, a bit stream A1 in an MPEG-2 format which is a first moving-image encoding-data format and side information A3 into a format suitable for an MPEG-4 format which is a second moving image encoding data format. Then, a bit stream A6 in an MPEG-4 format is obtained by encoding, by an MPEG-4 encoder, a converted reproduced image-signal A4 using motion vector information included in converted side information A5. At the same time, an indexing unit performs indexing using a motion vector included in the side information A5, and structured data A7 is obtained.
Patent Document 1: Japanese Patent Application Laid-open No. H8-186789
Patent Document 2: Japanese Patent Application Laid-open No. H9-294277
Patent Document 3: Japanese Patent Application Laid-open No. H10-257436
Patent Document 4: Japanese Patent Application Laid-open No. 2001-054106
Patent Document 5: Japanese Patent Application Laid-open No. 2002-185969